A bond example may display both a face value and a purchase price. They can differ, so a reader needs to know which amount is being used before following the calculation.
Read the contract amount separately
The SEC’s corporate bond bulletin explains face value, interest and bonds bought at prices different from face value. The promised payment terms do not eliminate default risk, and a sale before maturity can involve a different market price.
In a fictional example, label a face amount of 1,000 and a purchase price of 950 on separate lines. Do not call the difference a guaranteed gain without considering the terms, payments, costs and risks that the example includes or excludes.
Follow the author’s denominator
When a percentage appears, identify whether it is calculated from face value, purchase price or another measure. A coupon description and a return calculation are not interchangeable labels.
This is a reading exercise rather than a product recommendation. Its purpose is to keep each number connected to its role, so that an attractive-looking worked example can be examined on its stated assumptions instead of being treated as a promise.